Well I feel like I was at the point of no return. The plants have not showed any signs of improvement. I felt like I need to do something because it has been almost a week since the last reservoir change. In that last week there was little to no water used by the plants.
Last night (took me the entire night) I did a reservoir flush with distilled water (5 gallons) and used Clearx (7 TBS) and Big Bloom (5 TBS), Ph adjusted the water to 6.0, I ran the system with the pump on for 1.5 hours.
I drained the flush water after I seen the EC stop rising.
I topped the reservoir with 6 gallons of distilled water, Ph adjusted adjusted to 6.0, I added 10 tsp of Grow Big (3-2-6), and 5 TBS of Big Bloom, which brought my EC to a 1.0.
Today, 15 hours later, I still see no improvement in the two plants that are really struggling. The Ph did go up over night from 6.0 to 6.8 so I brought it down this AM to 6.0.
The only changes that I have made besides the res changes to try to find improvement are:
-Brought the 400 MH up a few more inches to make sure it isn't heat or light bleaching, the light is about 20 inch's above the plants.
-Removed that white towel, thinking maybe there was a chemical in the towel or something crazy.
-A couple of days ago I put a timer on the lights to go from 24/7 to 18/6, thinking that maybe the plants would benefit from the decreased temps and increase humidity for a few hours a day.
-I lowered the feeding tubes in the net pots, because the plants look to me to be showing signs of over watering.
-I did a res flush with Clearx last night, refilled the res with a EC of 1.0.
-Stopped misting the plants, seems to not be helping, and the problem started when I did start misting.
So, this brings me to what I'm thinking:
-My EC is supposed to be 1.6-1.8 according to the Fox Farm feeding schedule. JonnyB thinks that I'm underfeeding to start, I did my res change at 1.0 so this would be an extremely weak EC, am I correct about this? My thought is that the plants should start to show some signs of recovery, and I wanted to make sure that this problem wasn't from a over nute.
-Could I in fact be over watering? Maybe my air stones are not putting out as much air as they could? I'm tempted to remove the pump and feeder tubes. Thoughts?
-If I do not see any signs of improvement in the next few days, then the only other thing I can think to do is bring the EC up, to the feed schedule recommenced of 1.6-1.8.